Dental glass and dental composition

A dental glass comprising:

• phosphorus;
• sodium and or potassium;
• and
• calcium,
• wherein the dental glass contains, in terms of oxide,
• phosphorus (P2O5) by greater than or equal to 40% by mass and less than or equal to 70% by mass,
• sodium and/or potassium (Na2O, K2O) by greater than or equal to 25% by mass and less than or equal to 40% by mass, and
• calcium (CaO) by greater than or equal to 1% by mass and less than or equal to 20% by mass, and
• wherein the dental glass does not substantially contain silicon and aluminum.

A dental composition comprising:

• a dental glass;
• and
• a (meth)acrylate,
• wherein the dental glass contains, in terms of oxide,
• phosphorus (P2O5) by greater than or equal to 40% by mass and less than or equal to 70% by mass,
• sodium and/or potassium (Na2O, K2O) by greater than or equal to 20% by mass and less than or equal to 40% by mass, and
• calcium (CaO) by greater than or equal to 1% by mass and less than or equal to 20% by mass, and
• wherein the dental glass does not substantially contain silicon and aluminum.